Abstract: The process conditions for low-molecular peptides prepared by enzymatic hydrolyzation from broken rice were researched. Firstly, single factor experiments were used to confirm the main factors and their value scales affecting peptide yield rate. Based on this result, response surface methodology (RSM) was applied to optimize enzyme dosage, temperature and pH, and the second-order equation model for the yield of peptides was established. The optimal parameters for peptides yielding by acid protease hydrolyzation was 5272U/g of enzyme dosage , 54 ℃ of reaction temperature and pH4 . 26 . With 1 ∶ 20 of solid - liquid ratio and 2 hours hydrolyzing, the peptides yielding was up to 18.92%, which was nearly in agreed with the theoretical prediction value. The results suggested the predicted model was reliable and would provide some theoretic reference for the practical producing of broken rice peptides by enzymatic hydrolyzing .